Solid-state light sources, such as light emitting diodes (LED), are frequently used in luminaires because such light sources have a high luminous efficacy and a long lifetime. For many white LEDs used in general lighting applications such as road lighting and office lighting, the correlated color temperature (CCT) of the light radiation emitted therefrom is greater than or equal to 5000K. This light radiation may cause discomfort glare to users, especially under conditions where a high luminous intensity of the light radiation is required, such as road lighting. Therefore, many luminaires are designed to cut off their light radiation at the high incident angle, i.e. the direction of luminous intensity γ in the coordinate system in accordance with CIE140-2010, so as to reduce such discomfort glare. However, the cut-off light radiation may adversely influence the performance of such luminaires.